Sensor histidine kinase of Staphylococcus aureus

ABSTRACT

The invention provides Histidine Kinase polypeptides and polynucleotides encoding Histidine Kinase polypeptides and methods for producing such polypeptides by recombinant techniques. Also provided are methods for utilizing Histidine Kinase polypeptides or polynucleotides to screen for antibacterial compounds.

RELATED APPLICATIONS

This application claims benefit of U.S. Provisional Application Ser. No. 60/039,478 filed Feb. 25, 1997.

FIELD OF THE INVENTION

This invention relates to newly identified polynucleotides and polypeptides, and their production and uses, as well as their variants, agonists and antagonists, and their uses. In particular, in these and in other regards, the invention relates to novel polynucleotides and polypeptides of the histidine kinase family, hereinafter referred to as "Histidine Kinase".

BACKGROUND OF THE INVENTION

It is particularly preferred to employ Staphylococcal genes and gene products as targets for the development of antibiotics. The Staphylococci make up a medically important genera of microbes. They are known to produce two types of disease, invasive and toxigenic. Invasive infections are characterized generally by abscess formation effecting both skin surfaces and deep tissues. S. aureus is the second leading cause of bacteremia in cancer patients. Osteomyelitis, septic arthritis, septic thrombophlebitis and acute bacterial endocarditis are also relatively common. There are at least three clinical conditions resulting from the toxigenic properties of Staphylococci. The manifestation of these diseases result from the actions of exotoxins as opposed to tissue invasion and bacteremia. These conditions include: Staphylococcal food poisoning, scalded skin syndrome and toxic shock syndrome.

The frequency of Staphylococcus aureus infections has risen dramatically in the past 20 years. This has been attributed to the emergence of multiply antibiotic resistant strains and an increasing population of people with weakened immune systems. It is no longer uncommon to isolate Staphylococcus aureus strains which are resistant to some or all of the standard antibiotics. This has created a demand for both new anti-microbial agents and diagnostic tests for this organism.

Many two component signal transduction systems (TCSTS) have been identified in bacteria (Stock, J. B., Ninfa, A. J. & Stock, A. M. (1989) Microbiol. Rev. 53, 450-490). These are involved in the bacterium's ability to monitor its surroundings and adapt to changes in its environment. Several of these bacterial TCSTS are involved in virulence and bacterial pathogenesis within the host.

Histidine kinases are components of the TCSTS which autophosphorylate at a histidine residue. The phosphate group is then transferred to the cognate response regulator. The histidine kinases have five short conserved amino acid sequences (Stock, J. B., Ninfa, A. J. & Stock, A. M. (1989) Microbiol. Rev. 53, 450-490, Swanson, R. V., Alex, L. A. & Simon, M. I. (1994) TIBS 19 485-491). These are the histidine residue, which is phosphorylated, followed after approximately 100 residues by a conserved asparagine residue. After another 15 to 45 residues a DXGXG motif is found, followed by a FXXF motif after another 10-20 residues. 10-20 residues further on another glycine motif, GXG is found. The two glycine motifs are thought to be involved in nucleotide binding. This family of histidine kinases includes FixL protein from Rhizobium meliloti. FixL is the histidine kinase of the Fix TCSTS which is involved in sensing oxygen concentrations (David, M., Daveran M.-L., Batut J., Dedieu A., Domergue O., Ghai J., Hertig C., Boistard P. & Kahn D. (1988), Cell 54:671-683).

Response regulators are components of the TCSTS. These proteins are phosphorylated from histidine kinases and in turn once phosphorylated affect the response, often through a DNA binding domain becoming activated. The response regulators are characterized by a conserved N-terminal domain of approximately 100 amino acids. The N-terminal domains of response regulators as well as retaining five functionally important residues, corresponding to the residues D12, D13, D57, T87, K109 in CheY (Matsumura, P., Rydel, J. J., Linzmeier, R. & Vacante, D. (1984) J. Bacteriol. 160, 36-41), have conserved structural features (Volz, K. (1993) Biochemistry 32, 11741-11753). The 3-dimensional structures of CheY from Salmonella typhimurium (Stock, A. M., Mottonen, J. M., Stock, J. B. & Schutt, C. E. (1989) Nature, 337, 745-749) and Escherichia coli (Volz, K. & Matsumura, P. (1991) J. Biol. Chem. 266, 15511-15519) and the N-terminal domain of nitrogen regulatory protein C from S. typhimurium (Volkman, B. F., Nohaile, M. J., Amy, N. K., Kustu, S. & Wemmer, D. E. (1995) Biochemistry, 34 1413-1424), are available, as well as the secondary structure of SpoOF from Bacillus subtilis (Feher, V. A., Zapf, J. W., Hoch, J. A., Dahlquist, F. W., Whiteley, J. M. & Cavanagh, J. (1995) Protein Science, 4, 1801-1814). These structures have a (a/b) 5 fold. Several structural residues are conserved between different response regulator sequences, specifically hydrophobic residues within the β-sheet hydrophobic core and sites from the a-helices.

Among the processes regulated by TCSTS are production of virulence factors, motility, antibiotic resistance and cell replication. Inhibitors of TCSTS proteins would prevent the bacterium from establishing and maintaining infection of the host by preventing it from producing the necessary factors for pathogenesis and thereby have utility in anti-bacterial therapy.

Clearly, there is a need for factors, such as the novel compounds of the invention, having a present benefit of being useful to screen compounds for antibiotic activity. Such factors may also be used to determine their role in pathogenesis of infection, dysfunction and disease. There is also a need for identification and characterization of such factors and their antagonists and agonists which can play a role in preventing, ameliorating or correcting infections, dysfunctions or diseases.

The polypeptides of the invention have amino acid sequence homology to a known E. coli KdpD histidine kinase protein.

SUMMARY OF THE INVENTION

It is an object of the invention to provide polypeptides that have been identified as novel Histidine Kinase polypeptides by homology between the amino acid sequence set out in FIG. 2 [SEQ ID NO: 2] and a known amino acid sequence or sequences of other proteins such as E. coli KdpD histidine kinase protein.

It is a further object of the invention to provide polynucleotides that encode Histidine Kinase polypeptides, particularly polynucleotides that encode the polypeptide herein designated Histidine Kinase.

In a particularly preferred embodiment of the invention the polynucleotide comprises a region encoding Histidine Kinase polypeptides comprising the sequence set out in FIG. 1 [SEQ ID NO: 1], or a variant thereof.

In another particularly preferred embodiment of the invention there is a novel Histidine Kinase protein from Staphylococcus aureus comprising the amino acid sequence of FIG. 2 [SEQ ID NO:2], or a variant thereof.

In accordance with another aspect of the invention there is provided an isolated nucleic acid molecule encoding a mature polypeptide expressible by the Staphylococcus aureus WCUH 29 strain contained in NCIMB Deposit No. 40771.

A further aspect of the invention there are provided isolated nucleic acid molecules encoding Histidine Kinase, particularly Staphylococcus aureus Histidine Kinase, including mRNAs, cDNAs, genomic DNAs. Further embodiments of the invention include biologically, diagnostically, prophylactically, clinically or therapeutically useful variants thereof, and compositions comprising the same.

In accordance with another aspect of the invention, there is provided the use of a polynucleotide of the invention for therapeutic or prophylactic purposes, in particular genetic immunization. Among the particularly preferred embodiments of the invention are naturally occurring allelic variants of Histidine Kinase and polypeptides encoded thereby.

Another aspect of the invention there are provided novel polypeptides of Staphylococcus aureus referred to herein as Histidine Kinase as well as biologically, diagnostically, prophylactically, clinically or therapeutically useful variants thereof, and compositions comprising the same.

Among the particularly preferred embodiments of the invention are variants of Histidine Kinase polypeptide encoded by naturally occurring alleles of the Histidine Kinase gene.

In a preferred embodiment of the invention there are provided methods for producing the aforementioned Histidine Kinase polypeptides.

In accordance with yet another aspect of the invention, there are provided inhibitors to such polypeptides, useful as antibacterial agents, including, for example, antibodies.

In accordance with certain preferred embodiments of the invention, there are provided products, compositions and methods for assessing Histidine Kinase expression, treating disease, for example, disease, such as, infections of the upper respiratory tract (e.g., otitis media, bacterial tracheitis, acute epiglottitis, thyroiditis), lower respiratory (e.g., empyema, lung abscess), cardiac (e.g., infective endocarditis), gastrointestinal (e.g., secretory diarrhoea, splenic absces, retroperitoneal abscess), CNS (e.g., cerebral abscess), eye (e.g., blepharitis, conjunctivitis, keratitis, endophthalmitis, preseptal and orbital cellulitis, darcryocystitis), kidney and urinary tract (e.g., epididymitis, intrarenal and perinepbric absces, toxic shock syndrome), skin (e.g., impetigo, folliculitis, cutaneous abscesses, cellulitis, wound infection, bacterial myositis) bone and joint (e.g., septic arthritis, osteomyelitis), assaying genetic variation, and administering a Histidine Kinase polypeptide or polynucleotide to an organism to raise an immunological response against a bacteria, especially a Staphylococcus aureus bacteria.

In accordance with certain preferred embodiments of this and other aspects of the invention there are provided polynucleotides that hybridize to Histidine Kinase polynucleotide sequences, particularly under stringent conditions.

In certain preferred embodiments of the invention there are provided antibodies against Histidine Kinase polypeptides.

In accordance with yet another aspect of the invention, there are provided Histidine Kinase agonists and antagonists, preferably bacteriostatic or bacteriocidal agonists and antagonists.

In a further aspect of the invention there are provided compositions comprising a Histidine Kinase polynucleotide or a Histidine Kinase polypeptide for administration to a cell or to a multicellular organism.

Various changes and modifications within the spirit and scope of the disclosed invention will become readily apparent to those skilled in the art from reading the following descriptions and from reading the other parts of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings depict certain embodiments of the invention. They are illustrative only and do not limit the invention otherwise disclosed herein.

FIG. 1 shows the polynucleotide sequence of Staphylococcus aureus Histidine Kinase [SEQ ID NO: 1]. The complement of the start codon is shown underlined and the open reading frame is in the reverse direction of SEQ ID NO: 1.

FIG. 2 shows the amino acid sequence of Staphylococcus aureus Histidine Kinase [SEQ ID NO: 2] deduced from the reverse strand of the polynucleotide sequence of FIG. 1.

FIG. 3 shows the nucleic acid sequences [SEQ ID NO: 3] of the gene of the cognate response regulator of the invention. The start codon (ATG) is bold and underlined. The stop codon (TAA) is underlined.

FIG. 4 shows the amino acid sequence [SEQ ID NO: 4] of the polypeptide of the response regulator set forth in FIG. 3.

GLOSSARY

The following definitions are provided to facilitate understanding of certain terms used frequently herein.

"Host cell" is a cell which has been transformed or transfected, or is capable of transformation or transfection by an exogenous polynucleotide sequence.

"Identity," as known in the art, is a relationship between two or more polypeptide sequences or two or more polynucleotide sequences, as determined by comparing the sequences. In the art, "identity" also means the degree of sequence relatedness between polypeptide or polynucleotide sequences, as the case may be, as determined by the match between strings of such sequences. "Identity" and "similarity" can be readily calculated by known methods, including but not limited to those described in (Computational Molecular Biology, Lesk, A. M., ed., Oxford University Press, New York, 1988; Biocomputing: Informatics and Genome Projects, Smith, D. W., ed., Academic Press, New York, 1993; Computer Analysis of Sequence Data, Part I, Griffin, A. M., and Griffin, H. G., eds., Humana Press, New Jersey, 1994; Sequence Analysis in Molecular Biology, von Heinje, G., Academic Press, 1987; and Sequence Analysis Primer, Gribskov, M. and Devereux, J., eds., M Stockton Press, New York, 1991; and Carillo, H., and Lipman, D., SIAM J. Applied Math., 48: 1073 (1988). Preferred methods to determine identity are designed to give the largest match between the sequences tested. Methods to determine identity and similarity are codified in publicly available computer programs. Preferred computer program methods to determine identity and similarity between two sequences include, but are not limited to, the GCG program package (Devereux, J., et al., Nucleic Acids Research 12(1): 387 (1984)), BLASTP, BLASTN, and FASTA (Atschul, S. F. et al., J. Molec. Biol. 215: 403-410 (1990). The BLAST X program is publicly available from NCBI and other sources (BLAST Manual, Altschul, S., et al., NCBI NLM NIH Bethesda, Md. 20894; Altschul, S., et al., J. Mol. Biol. 215: 403-410 (1990). The well known Smith Waterman algorithm may also be used to determine identity.

Preferred parameters for polypeptide sequence comparison include the following:

1) Algorithm: Needleman and Wunsch, J. Mol Biol. 48: 443-453 (1970)

Comparison matrix: BLOSSUM62 from Hentikoff and Hentikoff, Proc. Natl. Acad. Sci. USA. 89:10915-10919 (1992)

Gap Penalty: 12

Gap Length Penalty: 4

A program useful with these parameters is publicly available as the "gap" program from Genetics Computer Group, Madison, Wis. The aforementioed parameters are the default parameters for peptide comparisons (along with no penalty for end gaps).

Preferred parameters for polynucleotide comparison include the following:

1) Algorithm: Needleman and Wunsch, J. Mol Biol. 48: 443-453 (1970)

Comparison matrix: matches=+10, mismatch=0

Gap Penalty: 50

Gap Length Penalty: 3

Available as: The "gap" program from Genetics Computer Group, Madison, Wis. These are the default parameters for nucleic acid comparisons.

Preferred polynucleotide embodiments further include an isolated polynucleotide comprising a polynucleotide having at least a 50, 60, 70, 80, 85, 90, 95, 97 or 100% identity to a polynucleotide reference sequence of SEQ ID NO: 1, wherein said reference sequence may be identical to the sequence of SEQ ID NO: 1 or may include up to a certain integer number of nucleotide alterations as compared to the reference sequence, wherein said alterations are selected from the group consisting of at least one nucleotide deletion, substitution, including transition and transversion, or insertion, and wherein said alterations may occur at the 5' or 3' terminal positions of the reference nucleotide sequence or anywhere between those terminal positions, interspersed either individually among the nucleotides in the reference sequence or in one or more contiguous groups within the reference sequence, and wherein said number of nucleotide alterations is determined by multiplying the total number of nucleotides in SEQ ID NO: 1 by the numerical percent of the respective percent identity and subtracting that product from said total number of nucleotides in SEQ ID NO: 1, or:

    n.sub.n ≦x.sub.n -(x.sub.n •y),

wherein n_(n) is the number of nucleotide alterations, x_(n) is the total number of nucleotides in SEQ ID NO: 1, and y is 0.50 for 50%, 0.60 for 60%, 0.70 for 70%, 0.80 for 80%, 0.85 for 85%, 0.90 for 90%, 0.95 for 95%, 0.97 for 97% or 1.00 for 100%, and wherein any non-integer product of x_(n) and y is rounded down to the nearest integer prior to subtracting it from x_(n). Alterations of a polynucleotide sequence encoding the polypeptide of SEQ ID NO: 2 may create nonsense, mis-sense or frameshift mutations in this coding sequence and thereby alter the polypeptide encoded by the polynucleotide following such alterations.

Preferred polypeptide embodiments further include an isolated polypeptide comprising a polypeptide having at least a 50, 60, 70, 80, 85, 90, 95, 97 or 100% identity to a polypeptide reference sequence of SEQ ID NO: 2, wherein said reference sequence may be identical to the sequence of SEQ ID NO: 2 or may include up to a certain integer number of amino acid alterations as compared to the reference sequence, wherein said alterations are selected from the group consisting of at least one amino acid deletion, substitution, including conservative and non-conservative substitution, or insertion, and wherein said alterations may occur at the amino- or carbxy-terminal positions of the reference polypeptide sequence or anywhere between those terminal positions, interspersed either individually among the aminno acids in the reference sequence or in one or more contiguous groups within the reference sequence, and wherein said number of amino acid alterations is determined by multiplying the total number of amino acids in SEQ ID NO: 2 by the numerical percent of the respective percent identity and subtracting that product from said total number of amino acids in SEQ ID NO: 2, or:

    n.sub.a ≦x.sub.a -(x.sub.a •y),

wherein n_(a) is the number of amino acid alterations, x_(a) is the total number of amino acids in SEQ ID NO: 2, and y is 0.50 for 50%, 0.60 for 60%, 0.70 for 70%, 0.80 for 80%, 0.85 for 85%, 0.90 for 90%, 0.95 for 95%, 0.97 for 97% or 1.00 for 100%, and wherein any non-integer product of x_(a) and y is rounded down to the nearest integer prior to subtracting it from x_(a).

"Isolated" means altered "by the hand of man" from its natural state, i.e., if it occurs in nature, it has been changed or removed from its original environment, or both. For example, a polynucleotide or a polypeptide naturally present in a living organism is not "isolated," but the same polynucleotide or polypeptide separated from the coexisting materials of its natural state is "isolated", as the term is employed herein.

"Polynucleotide(s)" generally refers to any polyribonucleotide or polydeoxribonucleotide, which may be unmodified RNA or DNA or modified RNA or DNA. "Polynucleotide(s)" include, without limitation, single- and double-stranded DNA, DNA that is a mixture of single- and double-stranded regions or single-, double- and triple-stranded regions, single- and double-stranded RNA, and RNA that is mixture of single- and double-stranded regions, hybrid molecules comprising DNA and RNA that may be single-stranded or, more typically, double-stranded, or triple-stranded regions, or a mixture of single- and double-stranded regions. In addition, "polynucleotide" as used herein refers to triple-stranded regions comprising RNA or DNA or both RNA and DNA. The strands in such regions may be from the same molecule or from different molecules. The regions may include all of one or more of the molecules, but more typically involve only a region of some of the molecules. One of the molecules of a triple-helical region often is an oligonucleotide. As used herein, the term "polynucleotide(s)" also includes DNAs or RNAs as described above that contain one or more modified bases. Thus, DNAs or RNAs with backbones modified for stability or for other reasons are "polynucleotide(s)" as that term is intended herein. Moreover, DNAs or RNAs comprising unusual bases, such as inosine, or modified bases, such as tritylated bases, to name just two examples, are polynucleotides as the term is used herein. It will be appreciated that a great variety of modifications have been made to DNA and RNA that serve many useful purposes known to those of skill in the art. The term "polynucleotide(s)" as it is employed herein embraces such chemically, enzymatically or metabolically modified forms of polynucleotides, as well as the chemical forms of DNA and RNA characteristic of viruses and cells, including, for example, simple and complex cells. "Polynucleotide(s)" also embraces short polynucleotides often referred to as oligonucleotide(s).

"Polypeptide(s)" refers to any peptide or protein comprising two or more amino acids joined to each other by peptide bonds or modified peptide bonds. "Polypeptide(s)" refers to both short chains, commonly referred to as peptides, oligopeptides and oligomers and to longer chains generally referred to as proteins. Polypeptides may contain amino acids other than the 20 gene encoded amino acids. "Polypeptide(s)" include those modified either by natural processes, such as processing and other post-translational modifications, but also by chemical modification techniques. Such modifications are well described in basic texts and in more detailed monographs, as well as in a voluminous research literature, and they are well known to those of skill in the art. It will be appreciated that the same type of modification may be present in the same or varying degree at several sites in a given polypeptide. Also, a given polypeptide may contain many types of modifications. Modifications can occur anywhere in a polypeptide, including the peptide backbone, the amino acid side-chains, and the amino or carboxyl termini. Modifications include, for example, acetylation, acylation, ADP-ribosylation, amidation, covalent attachment of flavin, covalent attachment of a heme moiety, covalent attachment of a nucleotide or nucleotide derivative, covalent attachment of a lipid or lipid derivative, covalent attachment of phosphotidylinositol, cross-linking, cyclization, disulfide bond formation, demethylation, formation of covalent cross-links, formation of cysteine, formation of pyroglutamate, formylation, gamma-carboxylation, glycosylation, GPI anchor formation, hydroxylation, iodination, methylation, myristoylation, oxidation, proteolytic processing, phosphorylation, prenylation, racemization, glycosylation, lipid attachment, sulfation, gamma-carboxylation of glutamic acid residues, hydroxylation and ADP-ribosylation, selenoylation, sulfation, transfer-RNA mediated addition of amino acids to proteins, such as arginylation, and ubiquitination. See, for instance, PROTEINS--STRUCTURE AND MOLECULAR PROPERTIES, 2nd Ed., T. E. Creighton, W. H. Freeman and Company, New York (1993) and Wold, F., Posttranslational Protein Modifications: Perspectives and Prospects, pgs. 1-12 in POSTTRANSLATIONAL COVALENT MODIFICATION OF PROTEINS, B. C. Johnson, Ed., Academic Press, New York (1983); Seifter et al., Meth. Enzymol. 182:626-646 (1990) and Rattan et al., Protein Synthesis: Posttranslational Modifications and Aging, Ann. N.Y. Acad. Sci. 663: 48-62 (1992). Polypeptides may be branched or cyclic, with or without branching. Cyclic, branched and branched circular polypeptides may result from post-translational natural processes and may be made by entirely synthetic methods, as well.

"Variant(s)" as the term is used herein, is a polynucleotide or polypeptide that differs from a reference polynucleotide or polypeptide respectively, but retains essential properties. A typical variant of a polynucleotide differs in nucleotide sequence from another, reference polynucleotide. Changes in the nucleotide sequence of the variant may or may not alter the amino acid sequence of a polypeptide encoded by the reference polynucleotide. Nucleotide changes may result in amino acid substitutions, additions, deletions, fusions and truncations in the polypeptide encoded by the reference sequence, as discussed below. A typical variant of a polypeptide differs in amino acid sequence from another, reference polypeptide. Generally, differences are limited so that the sequences of the reference polypeptide and the variant are closely similar overall and, in many regions, identical. A variant and reference polypeptide may differ in amino acid sequence by one or more substitutions, additions, deletions in any combination. A substituted or inserted amino acid residue may or may not be one encoded by the genetic code. A variant of a polynucleotide or polypeptide may be a naturally occurring such as an allelic variant, or it may be a variant that is not known to occur naturally. Non-naturally occurring variants of polynucleotides and polypeptides may be made by mutagenesis techniques, by direct synthesis, and by other recombinant methods known to skilled artisans.

DESCRIPTION OF THE INVENTION

The invention relates to novel Histidine Kinase polypeptides and polynucleotides as described in greater detail below. In particular, the invention relates to polypeptides and polynucleotides of a novel Histidine Kinase gene of Staphylococcus aureus, which is related by amino acid sequence homology to E. coli KdpD histidine kinase polypeptide. The invention relates especially to Histidine Kinase having the nucleotide and amino acid sequences set out in FIG. 1 [SEQ ID NO: 1] and FIG. 2 [SEQ ID NO: 2] respectively, and to the Histidine Kinase nucleotide sequences of the DNA deposited in NCIMB Deposit No. 40771 and amino acid sequences encoded thereby.

Deposited Materials

A deposit containing a Staphylococcus aureus WCUH 29 strain has been deposited with the National Collections of Industrial and Marine Bacteria Ltd. (NCIMB), 23 St. Machar Drive, Aberdeen AB2 1RY, Scotland on Sep. 11, 1995 and assigned NCIMB Deposit No. 40771. The Staphylococcus aureus strain deposit is referred to herein as "the deposited strain" or as "the DNA of the deposited strain."

The deposited material is a strain that contains the full length Histidine Kinase DNA, referred to as "NCIMB 40771" upon deposit. The sequence of the polynucleotides contained in the deposited material, as well as the amino acid sequence of the polypeptide encoded thereby, are controlling in the event of any conflict with any description of sequences herein.

The deposit has been made under the terms of the Budapest Treaty on the International Recognition of the Deposit of Micro-organisms for Purposes of Patent Procedure. The strain will be irrevocably and without restriction or condition released to the public upon the issuance of a patent. The deposit is provided merely as convenience to those of skill in the art and is not an admission that a deposit is required for enablement, such as that required under 35 U.S.C. § 112.

A license may be required to make, use or sell the deposited materials, and no such license is hereby granted.

Polypeptides

The polypeptides of the invention include the polypeptide of FIG. 2 [SEQ ID NO: 2] (in particular the mature polypeptide) as well as polypeptides and fragments, particularly those which have the biological activity of Histidine Kinase, and also those which have at least 70% identity to the polypeptide of FIG. 2 [SEQ ID NO: 2] or the relevant portion, preferably at least 80% identity to the polypeptide of FIG. 2 [SEQ ID NO: 2], and more preferably at least 90% similarity (more preferably at least 90% identity) to the polypeptide of FIG. 2 [SEQ ID NO: 2] and still more preferably at least 95% similarity (still more preferably at least 95% identity) to the polypeptide of FIG. 2 [SEQ ID NO: 2] and also include portions of such polypeptides with such portion of the polypeptide generally containing at least 30 amino acids and more preferably at least 50 amino acids.

A fragment is a variant polypeptide having an amino acid sequence that entirely is the same as part but not all of the amino acid sequence of the aforementioned polypeptides. As with Histidine Kinase polypeptides fragments may be "free-standing," or comprised within a larger polypeptide of which they form a part or region, most preferably as a single continuous region, a single larger polypeptide.

Preferred fragments include, for example, truncation polypeptides having a portion of the amino acid sequence of FIG. 2 [SEQ ID NO: 2], or of variants thereof, such as a continuous series of residues that includes the amino terminus, or a continuous series of residues that includes the carboxyl terminus. Degradation forms of the polypeptides of the invention in a host cell, particularly a Staphylococcus aureus, are also preferred. Further preferred are fragments characterized by structural or functional attributes such as fragments that comprise alpha-helix and alpha-helix forming regions, beta-sheet and beta-sheet-forming regions, turn and turn-forming regions, coil and coil-forming regions, hydrophilic regions, hydrophobic regions, alpha amphipathic regions, beta amphipathic regions, flexible regions, surface-forming regions, substrate binding region, and high antigenic index regions.

Also preferred are biologically active fragments which are those fragments that mediate activities of Histidine Kinase, including those with a similar activity or an improved activity, or with a decreased undesirable activity. Also included are those fragments that are antigenic or immunogenic in an animal, especially in a human. Particularly preferred are fragments comprising receptors or domains of enzymes that confer a function essential for viability of Staphylococcus aureus or the ability to initiate, or maintain cause disease in an individual, particularly a human.

Variants that are fragments of the polypeptides of the invention may be employed for producing the corresponding full-length polypeptide by peptide synthesis; therefore, these variants may be employed as intermediates for producing the full-length polypeptides of the invention.

Polynucleotides

Another aspect of the invention relates to isolated polynucleotides that encode the Histidine Kinase polypeptide having the deduced amino acid sequence of FIG. 2 [SEQ ID NO: 2] and polynucleotides closely related thereto and variants thereof.

Using the information provided herein, such as the polynucleotide sequence set out in FIG. 1 [SEQ ID NO: 1], a polynucleotide of the invention encoding Histidine Kinase polypeptide may be obtained using standard cloning and screening methods, such as those for cloning and sequencing chromosomal DNA fragments from bacteria using Staphylococcus aureus WCUH 29 cells as starting material, followed by obtaining a full length clone. For example, to obtain a polynucleotide sequence of the invention, such as the sequence given in FIG. 1 [SEQ ID NO: 1], typically a library of clones of chromosomal DNA of Staphylococcus aureus WCUH 29 in E. coli or some other suitable host is probed with a radiolabeled oligonucleotide, preferably a 17-mer or longer, derived from a partial sequence. Clones carrying DNA identical to that of the probe can then be distinguished using stringent conditions. By sequencing the individual clones thus identified with sequencing primers designed from the original sequence it is then possible to extend the sequence in both directions to determine the full gene sequence. Conveniently, such sequencing is performed using denatured double stranded DNA prepared from a plasmid clone. Suitable techniques are described by Maniatis, T., Fritsch, E. F. and Sambrook et al., MOLECULAR CLONING, A LABORATORY MANUAL, 2nd Ed.; Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (1989) (see in particular Screening By Hybridization 1.90 and Sequencing Denatured Double-Stranded DNA Templates 13.70). Illustrative of the invention, the polynucleotide set out in FIG. 1 [SEQ ID NO: 1] was discovered in a DNA library derived from Staphylococcus aureus WCUH 29.

The DNA sequence set out in FIG. 1 [ SEQ ID NO: 1] contains an open reading frame encoding a protein having about the number of amino acid residues set forth in FIG. 2 [SEQ ID NO: 2] with a deduced molecular weight that can be calculated using amino acid residue molecular weight values well known in the art. Histidine Kinase of the invention is structurally related to other proteins of the histidine kinase family, as shown by the results of sequencing the DNA encoding Histidine Kinase of the deposited strain. The protein exhibits greatest homology to E. coli KdpD histidine kinase protein among known proteins. Histidine Kinase of FIG. 2 [SEQ ID NO: 2] has about 27% identity over its entire length with the amino acid sequence of E. coli KdpD histidine kinase polypeptide.

The invention provides a polynucleotide sequence identical over its entire length to the coding sequence in FIG. 1 [SEQ ID NO: 1]. Also provided by the invention is the coding sequence for the mature polypeptide or a fragment thereof, by itself as well as the coding sequence for the mature polypeptide or a fragment in reading frame with other coding sequence, such as those encoding a leader or secretory sequence, a pre-, or pro- or prepro- protein sequence. The polynucleotide may also contain non-coding sequences, including for example, but not limited to non-coding 5' and 3' sequences, such as the transcribed, non-translated sequences, termination signals, ribosome binding sites, sequences that stabilize mRNA, introns, polyadenylation signals, and additional coding sequence which encode additional amino acids. For example, a marker sequence that facilitates purification of the fused polypeptide can be encoded. In certain embodiments of the invention, the marker sequence is a hexa-histidine peptide, as provided in the pQE vector (Qiagen, Inc.) and described in Gentz et al., Proc. Natl. Acad. Sci., USA 86: 821-824 (1989), or an HA tag (Wilson et al., Cell 37: 767 (1984). Polynucleotides of the invention also include, but are not limited to, polynucleotides comprising a structural gene and its naturally associated sequences that control gene expression.

The term "polynucleotide encoding a polypeptide" as used herein encompasses polynucleotides that include a sequence encoding a polypeptide of the invention, particularly a bacterial polypeptide and more particularly a polypeptide of the Staphylococcus aureus Histidine Kinase having the amino acid sequence set out in FIG. 2 [SEQ ID NO: 2]. The term also encompasses polynucleotides that include a single continuous region or discontinuous regions encoding the polypeptide (for example, interrupted by integrated phage or an insertion sequence or editing) together with additional regions, that also may contain coding and/or non-coding sequences.

The invention further relates to variants of the polynucleotides described herein that encode for variants of the polypeptide having the deduced amino acid sequence of FIG. 2 [SEQ ID NO: 2]. Variants that are fragments of the polynucleotides of the invention may be used to synthesize full-length polynucleotides of the invention.

Further particularly preferred embodiments are polynucleotides encoding Histidine Kinase variants, that have the amino acid sequence of Histidine Kinase polypeptide of FIG. 2 [SEQ ID NO: 2] in which several, a few, 5 to 10, 1 to 5, 1 to 3, 2, 1 or no amino acid residues are substituted, deleted or added, in any combination. Especially preferred among these are silent substitutions, additions and deletions, that do not alter the properties and activities of Histidine Kinase.

Further preferred embodiments of the invention are polynucleotides that are at least 70% identical over their entire length to a polynucleotide encoding Histidine Kinase polypeptide having the amino acid sequence set out in FIG. 2 [SEQ ID NO: 2], and polynucleotides that are complementary to such polynucleotides. Alternatively, most highly preferred are polynucleotides that comprise a region that is at least 80% identical over its entire length to a polynucleotide encoding Histidine Kinase polypeptide of the deposited strain and polynucleotides complementary thereto. In this regard, polynucleotides at least 90% identical over their entire length to the same are particularly preferred, and among these particularly preferred polynucleotides, those with at least 95% are especially preferred. Furthermore, those with at least 97% are highly preferred among those with at least 95%, and among these those with at least 98% and at least 99% are particularly highly preferred, with at least 99% being the more preferred.

Preferred embodiments are polynucleotides that encode polypeptides that retain substantially the same biological function or activity as the mature polypeptide encoded by the DNA of FIG. 1 [SEQ ID NO: 1].

The invention further relates to polynucleotides that hybridize to the herein above-described sequences. In this regard, the invention especially relates to polynucleotides that hybridize under stringent conditions to the herein above-described polynucleotides. As herein used, the terms "stringent conditions" and "stringent hybridization conditions" mean hybridization will occur only if there is at least 95% and preferably at least 97% identity between the sequences. An example of stringent hybridization conditions is overnight incubation at 42° C. in a solution comprising: 50% formamide, 5× SSC (150 mM NaCl, 15 mM trisodium citrate), 50 mM sodium phosphate (pH 7.6), 5× Denhardt's solution, 10% dextran sulfate, and 20 micrograms/ml denatured, sheared salmon sperm DNA, followed by washing the hybridization support in 0.1× SSC at about 65° C. Hybridization and wash conditions are well known and exemplified in Sambrook, et al., Molecular Cloning: A Laboratory Manual, Second Edition, Cold Spring Harbor, N.Y., (1989), particularly Chapter 11 therein.

The invention also provides a polynucleotide consisting essentially of a polynucleotide sequence obtainable by screening an appropriate library containing the complete gene for a polynucleotide sequence set forth in SEQ ID NO: 1 under stringent hybridization conditions with a probe having the sequence of said polynucleotide sequence set forth in SEQ ID NO: 1 or a fragment thereof; and isolating said DNA sequence. Fragments useful for obtaining such a polynucleotide include, for example, probes and primers described elsewhere herein.

As discussed additionally herein regarding polynucleotide assays of the invention, for instance, polynucleotides of the invention as discussed above, may be used as a hybridization probe for RNA, cDNA and genomic DNA to isolate full-length cDNAs and genomic clones encoding Histidine Kinase and to isolate cDNA and genomic clones of other genes that have a high sequence similarity to the Histidine Kinase gene. Such probes generally will comprise at least 15 bases. Preferably, such probes will have at least 30 bases and may have at least 50 bases. Particularly preferred probes will have at least 30 bases and will have 50 bases or less.

For example, the coding region of the Histidine Kinase gene may be isolated by screening using the known DNA sequence provided in SEQ ID NO: 1 to synthesize an oligonucleotide probe. A labeled oligonucleotide having a sequence complementary to that of a gene of the invention is then used to screen a library of cDNA, genomic DNA or mRNA to determine which members of the library the probe hybridizes to.

The polynucleotides and polypeptides of the invention may be employed, for example, as research reagents and materials for discovery of treatments of and diagnostics for disease, particularly human disease, as further discussed herein relating to polynucleotide assays.

Polynucleotides of the invention that are oligonucleotides derived from the sequences of SEQ ID NOS: 1 and/or 2 may be used in the processes herein as described, but preferably for PCR, to determine whether or not the polynucleotides identified herein in whole or in part are transcribed in bacteria in infected tissue. It is recognized that such sequences will also have utility in diagnosis of the stage of infection and type of infection the pathogen has attained.

The invention also provides polynucleotides that may encode a polypeptide that is the mature protein plus additional amino or carboxyl-terminal amino acids, or amino acids interior to the mature polypeptide (when the mature form has more than one polypeptide chain, for instance). Such sequences may play a role in processing of a protein from precursor to a mature form, may allow protein transport, may lengthen or shorten protein half-life or may facilitate manipulation of a protein for assay or production, among other things. As generally is the case in vivo, the additional amino acids may be processed away from the mature protein by cellular enzymes.

A precursor protein, having the mature form of the polypeptide fused to one or more prosequences may be an inactive form of the polypeptide. When prosequences are removed such inactive precursors generally are activated. Some or all of the prosequences may be removed before activation. Generally, such precursors are called proproteins.

In sum, a polynucleotide of the invention may encode a mature protein, a mature protein plus a leader sequence (which may be referred to as a preprotein), a precursor of a mature protein having one or more prosequences that are not the leader sequences of a preprotein, or a preproprotein, which is a precursor to a proprotein, having a leader sequence and one or more prosequences, which generally are removed during processing steps that produce active and mature forms of the polypeptide.

Vectors, Host Cells, Expression

The invention also relates to vectors that comprise a polynucleotide or polynucleotides of the invention, host cells that are genetically engineered with vectors of the invention and the production of polypeptides of the invention by recombinant techniques. Cell-free translation systems can also be employed to produce such proteins using RNAs derived from the DNA constructs of the invention.

For recombinant production, host cells can be genetically engineered to incorporate expression systems or portions thereof or polynucleotides of the invention. Introduction of a polynucleotide into the host cell can be effected by methods described in many standard laboratory manuals, such as Davis et al., BASIC METHODS IN MOLECULAR BIOLOGY, (1986) and Sambrook et al., MOLECULAR CLONING: A LABORATORY MANUAL, 2nd Ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (1989), such as, calcium phosphate transfection, DEAE-dextran mediated transfection, transvection, microinjection, cationic lipid-mediated transfection, electroporation, transduction, scrape loading, ballistic introduction and infection.

Representative examples of appropriate hosts include bacterial cells, such as streptococci, staphylococci, enterococci E. coli, streptomyces and Bacillus subtilis cells; fungal cells, such as yeast cells and Aspergillus cells; insect cells such as Drosophila S2 and Spodoptera Sf9 cells; animal cells such as CHO, COS, HeLa, C127, 3T3, BHK, 293 and Bowes melanoma cells; and plant cells.

A great variety of expression systems can be used to produce the polypeptides of the invention. Such vectors include, among others, chromosomal, episomal and virus-derived vectors, e.g., vectors derived from bacterial plasmids, from bacteriophage, from transposons, from yeast episomes, from insertion elements, from yeast chromosomal elements, from viruses such as baculoviruses, papova viruses, such as SV40, vaccinia viruses, adenoviruses, fowl pox viruses, pseudorabies viruses and retroviruses, and vectors derived from combinations thereof, such as those derived from plasmid and bacteriophage genetic elements, such as cosmids and phagemids. The expression system constructs may contain control regions that regulate as well as engender expression. Generally, any system or vector suitable to maintain, propagate or express polynucleotides and/or to express a polypeptide in a host may be used for expression in this regard. The appropriate DNA sequence may be inserted into the expression system by any of a variety of well-known and routine techniques, such as, for example, those set forth in Sambrook et al., MOLECULAR CLONING, A LABORATORY MANUAL, (supra).

For secretion of the translated protein into the lumen of the endoplasmic reticulum, into the periplasmic space or into the extracellular environment, appropriate secretion signals may be incorporated into the expressed polypeptide. These signals may be endogenous to the polypeptide or they may be heterologous signals.

Polypeptides of the invention can be recovered and purified from recombinant cell cultures by well-known methods including ammonium sulfate or ethanol precipitation, acid extraction, anion or cation exchange chromatography, phosphocellulose chromatography, hydrophobic interaction chromatography, affinity chromatography, hydroxylapatite chromatography, and lectin chromatography. Most preferably, high performance liquid chromatography is employed for purification. Well known techniques for refolding protein may be employed to regenerate active conformation when the polypeptide is denatured during isolation and or purification.

Diagnostic Assays

This invention is also related to the use of the Histidine Kinase polynucleotides of the invention for use as diagnostic reagents. Detection of Histidine Kinase in a eukaryote, particularly a mammal, and especially a human, will provide a diagnostic method for diagnosis of a disease. Eukaryotes (herein also "individual(s)"), particularly mammals, and especially humans, infected with an organism comprising the Histidine Kinase gene may be detected at the nucleic acid level by a variety of techniques.

Nucleic acids for diagnosis may be obtained from an infected individual's cells and tissues, such as bone, blood, muscle, cartilage, and skin. Genomic DNA may be used directly for detection or may be amplified enzymatically by using PCR or other amplification technique prior to analysis. RNA or cDNA may also be used in the same ways. Using amplification, characterization of the species and strain of prokaryote present in an individual, may be made by an analysis of the genotype of the prokaryote gene. Deletions and insertions can be detected by a change in size of the amplified product in comparison to the genotype of a reference sequence. Point mutations can be identified by hybridizing amplified DNA to labeled Histidine Kinase polynucleotide sequences. Perfectly matched sequences can be distinguished from mismatched duplexes by RNase digestion or by differences in melting temperatures. DNA sequence differences may also be detected by alterations in the electrophoretic mobility of the DNA fragments in gels, with or without denaturing agents, or by direct DNA sequencing. See, e.g., Myers et al., Science, 230: 1242 (1985). Sequence changes at specific locations also may be revealed by nuclease protection assays, such as RNase and S1 protection or a chemical cleavage method. See, e.g., Cotton et al., Proc. Natl. Acad. Sci., USA, 85: 4397-4401 (1985).

Cells carrying mutations or polymorphisms in the gene of the invention may also be detected at the DNA level by a variety of techniques, to allow for serotyping, for example. For example, RT-PCR can be used to detect mutations. It is particularly preferred to used RT-PCR in conjunction with automated detection systems, such as, for example, GeneScan. RNA or cDNA may also be used for the same purpose, PCR or RT-PCR. As an example, PCR primers complementary to a nucleic acid encoding Histidine Kinase can be used to identify and analyze mutations. These primers may also be used for amplifying Histidine Kinase DNA isolated from a sample derived from an individual. The invention further provides these primers with 1, 2, 3 or 4 nucleotides removed from the 5' and/or the 3' end. The primers may be used to amplify the gene isolated from an infected individual such that the gene may then be subject to various techniques for elucidation of the DNA sequence. In this way, mutations in the DNA sequence may be detected and used to diagnose infection and to serotype and/or classify the infectious agent.

The invention further provides a process for diagnosing, disease, preferably bacterial infections, more preferably infections by Staphylococcus aureus, and most preferably disease, such as, infections of the upper respiratory tract (e.g., otitis media, bacterial tracheitis, acute epiglottitis, thyroiditis), lower respiratory (e.g., empyema, lung abscess), cardiac (e.g., infective endocarditis), gastrointestinal (e.g., secretory diarrhoea, splenic absces, retroperitoneal abscess), CNS (e.g., cerebral abscess), eye (e.g., blepharitis, conjunctivitis, keratitis, endophthalmitis, preseptal and orbital cellulitis, darcryocystitis), kidney and urinary tract (e.g., epididymitis, intrarenal and perinephric absces, toxic shock syndrome), skin (e.g., impetigo, folliculitis, cutaneous abscesses, cellulitis, wound infection, bacterial myositis) bone and joint (e.g., septic arthritis, osteomyelitis), comprising determining from a sample derived from an individual a increased level of expression of polynucleotide having the sequence of FIG. 1 [SEQ ID NO: 1]. Increased or decreased expression of Histidine Kinase polynucleotide can be measured using any on of the methods well known in the art for the quantitation of polynucleotides, such as, for example, amplification, PCR, RT-PCR, RNase protection, Northern blotting and other hybridization methods.

In addition, a diagnostic assay in accordance with the invention for detecting over-expression of Histidine Kinase protein compared to normal control tissue samples may be used to detect the presence of an infection, for example. Assay techniques that can be used to determine levels of a Histidine Kinase protein, in a sample derived from a host are well-known to those of skill in the art. Such assay methods include radioimmunoassays, competitive-binding assays, Western Blot analysis and ELISA assays.

Antibodies

The polypeptides of the invention or variants thereof, or cells expressing them can be used as an immunogen to produce antibodies immunospecific for such polypeptides. "Antibodies" as used herein includes monoclonal and polyclonal antibodies, chimeric, single chain, simianized antibodies and humanized antibodies, as well as Fab fragments, including the products of an Fab immunolglobulin expression library.

Antibodies generated against the polypeptides of the invention can be obtained by administering the polypeptides or epitope-bearing fragments, analogues or cells to an animal, preferably a nonhuman, using routine protocols. For preparation of monoclonal antibodies, any technique known in the art that provides antibodies produced by continuous cell line cultures can be used. Examples include various techniques, such as those in Kohler, G. and Milstein, C., Nature 256: 495-497 (1975); Kozbor et al., Immunology Today 4: 72 (1983); Cole et al., pg. 77-96 in MONOCLONAL ANTIBODIES AND CANCER THERAPY, Alan R. Liss, Inc. (1985).

Techniques for the production of single chain antibodies (U.S. Pat. No. 4,946,778) can be adapted to produce single chain antibodies to polypeptides of this invention. Also, transgenic mice, or other organisms such as other mammals, may be used to express humanized antibodies.

Alternatively phage display technology may be utilized to select antibody genes with binding activities towards the polypeptide either from repertoires of PCR amplified v-genes of lymphocytes from humans screened for possessing anti-Histidine Kinase or from naive libraries (McCafferty, J. et al., (1990), Nature 348, 552-554; Marks, J. et al., (1992) Biotechnology 10, 779-783). The affinity of these antibodies can also be improved by chain shuffling (Clackson, T. et al., (1991) Nature 352, 624-628).

If two antigen binding domains are present each domain may be directed against a different epitope--termed `bispecific` antibodies.

The above-described antibodies may be employed to isolate or to identify clones expressing the polypeptides to purify the polypeptides by affinity chromatography.

Thus, among others, antibodies against Histidine Kinase- polypeptide may be employed to treat infections, particularly bacterial infections and especially disease, such as, infections of the upper respiratory tract (e.g., otitis media, bacterial tracheitis, acute epiglottitis, thyroiditis), lower respiratory (e.g., empyema, lung abscess), cardiac (e.g., infective endocarditis), gastrointestinal (e.g., secretory diarrhoea, splenic absces, retroperitoneal abscess), CNS (e.g., cerebral abscess), eye (e.g., blepharitis, conjunctivitis, keratitis, endophthalmitis, preseptal and orbital cellulitis, darcryocystitis), kidney and urinary tract (e.g., epididymitis, intrarenal and perinephric absces, toxic shock syndrome), skin (e.g., impetigo, folliculitis, cutaneous abscesses, cellulitis, wound infection, bacterial myositis) bone and joint (e.g., septic arthritis, osteomyelitis).

Polypeptide variants include antigenically, epitopically or immunologically equivalent variants that form a particular aspect of this invention. The term "antigenically equivalent derivative" as used herein encompasses a polypeptide or its equivalent which will be specifically recognized by certain antibodies which, when raised to the protein or polypeptide according to the invention, interfere with the immediate physical interaction between pathogen and mammalian host. The term "immunologically equivalent derivative" as used herein encompasses a peptide or its equivalent which when used in a suitable formulation to raise antibodies in a vertebrate, the antibodies act to interfere with the immediate physical interaction between pathogen and mammalian host.

The polypeptide, such as an antigenically or immunologically equivalent derivative or a fusion protein thereof is used as an antigen to immunize a mouse or other animal such as a rat or chicken. The fusion protein may provide stability to the polypeptide. The antigen may be associated, for example by conjugation, with an immunogenic carrier protein for example bovine serum albumin (BSA) or keyhole limpet haemocyanin (KLH). Alternatively a multiple antigenic peptide comprising multiple copies of the protein or polypeptide, or an antigenically or immunologically equivalent polypeptide thereof may be sufficiently antigenic to improve immunogenicity so as to obviate the use of a carrier.

Preferably, the antibody or variant thereof is modified to make it less immunogenic in the individual. For example, if the individual is human the antibody may most preferably be "humanized"; where the complimentarity determining region(s) of the hybridoma-derived antibody has been transplanted into a human monoclonal antibody, for example as described in Jones, P. et al. (1986), Nature 321, 522-525 or Tempest et al., (1991) Biotechnology 9, 266-273.

The use of a polynucleotide of the invention in genetic immunization will preferably employ a suitable delivery method such as direct injection of plasmid DNA into muscles (Wolff et al., Hum Mol Genet 1992, 1:363, Manthorpe et al., Hum. Gene Ther. 1963:4, 419), delivery of DNA complexed with specific protein carriers (Wu et al., J Biol Chem 1989:264,16985), coprecipitation of DNA with calcium phosphate (Benvenisty & Reshef, PNAS, 1986:83,9551), encapsulation of DNA in various forms of liposomes (Kaneda et al., Science 1989:243,375), particle bombardment (Tang et al., Nature 1992, 356:152, Eisenbraun et al., DNA Cell Biol 1993, 12:791) and in vivo infection using cloned retroviral vectors (Seeger et al., PNAS 1984:81,5849).

Antagonists and Agonists--Assays and Molecules

Each of the polynucleotide sequences provided herein, particularly the DNA sequences, may be used in the discovery and development of antibacterial compounds. For example, the encoded protein, upon expression, can be used as a target for the screening of antibacterial drugs. Additionally, the DNA sequences encoding the amino terminal regions of the encoded protein or Shine-Delgamo or other translation facilitating sequences of the respective mRNA can be used to construct antisense sequences to control the expression of the coding sequence of interest.

The invention also provides a method of screening compounds to identify those which enhance (agonist) or block (antagonist) the action of Histidine Kinase polypeptides or polynucleotides, particularly those compounds that are bacteriostatic and/or bacteriocidal. The method of screening may involve high-throughput techniques, including, for example, multiwell formats or multi-sample detection formats known to skilled artisans.

For example, to screen for agonists or antagonists, a synthetic reaction mix, a cellular compartment, such as a membrane, cell envelope or cell wall, or a preparation of any thereof, comprising Histidine Kinase polypeptide and a labeled substrate or ligand of such polypeptide is incubated in the absence or the presence of a candidate molecule that may be a Histidine Kinase agonist or antagonist. Synthetic reaction mixes useful in this aspect of the invention may comprise, among other things, purified or recombinantly expressed Histidine Kinase polypeptide or polynucleotide. The ability of the candidate molecule to agonize or antagonize the Histidine Kinase polypeptide or polynucleotide is reflected in decreased binding of the labeled ligand to such polypeptide or polynucleotide, or decreased production of product from such substrate by such polypeptide, or such polynucleotide, as with catalytic RNAs. Molecules that bind gratuitously, i.e., without inducing the effects of Histidine Kinase polypeptide are most likely to be good antagonists. Molecules that bind well and increase the rate of product production from substrate are most likely to be good agonists. Detection of the rate or level of production of product from substrate may be enhanced by using a reporter system. Reporter systems that may be useful in this regard include but are not limited to colorimetric labeled substrate to be converted into product, a reporter gene that is responsive to changes in Histidine Kinase, radiolabeled substrate, among others. It is preferred that these assays comprise the cognate response regulator of the histidine kinase of the invention. FIGS. 3 and 4, respectively, set forth the gene and protein sequence of this cognate response regulator. The response regulator open reading frame is in the forward orientation, with the start at nucleotide 14 and the end at nucleotide 709 of SEQ ID NO: 3. SEQ ID NO: 4 displays homology of 34% identity to the PhoP regulatory protein from Bacillus subtilis.

Another example of an assay for Histidine Kinase antagonists is a competitive assay that combines Histidine Kinase polypeptide or polynucleotide and a potential antagonist with Histidine Kinase-binding molecules (molecules that bind such polynucleotide or polypeptide), recombinant Histidine Kinase-binding molecules, natural substrates or ligands, or substrate or ligand mimetics, under appropriate conditions for a competitive inhibition assay. A preferred embodiment of this aspect of the invention also comprises the respose regulator. Histidine Kinase can be labeled, such as by radiolabeling or a colorimetric compound, such that the number of Histidine Kinase molecules bound to a Histidine Kinase-binding molecule or converted to product can be determined accurately to assess the effectiveness of the potential antagonist. Using the disclosures herein, skilled artisans may design and perform many types of competitive assay.

Potential antagonists include small organic molecules, peptides, peptide mimetics, polypeptides and antibodies that bind to a polynucleotide or polypeptide of the invention and preferably thereby inhibit or extinguish its activity. Potential antagonists also may be small organic molecules, a peptide, a peptide mimetic, a polypeptide, such as a closely related protein or antibody that binds the same sites on a Histidine Kinase-binding molecule without inducing Histidine Kinase-induced activities, thereby preventing the action of Histidine Kinase, such as by excluding Histidine Kinase from binding, and particularly by preventing the interaction of Histidine Kinase and its cognate respose regulator.

Potential antagonists include a small molecule that binds to and occupies the binding site of Histidine Kinase polypeptide or polynucleotide thereby preventing binding to cellular binding molecules, particularly response regulators, such that normal biological activity is prevented. Examples of small molecules include but are not limited to small organic molecules, peptides or peptide-like molecules, peptide mimetics. Other potential antagonists include antisense molecules (see Okano, J. Neurochem. 56: 560 (1991); OLIGODEOXYNUCLEOTIDES AS ANTISENSE INHIBITORS OF GENE EXPRESSION, CRC Press, Boca Raton, Fla. (1988), for a description of these molecules). Preferred potential antagonists include compounds related to and variants of Histidine Kinase, and compounds structurally related to known inhibitors of E. coli KdpD histidine kinase.

Polypeptides of the invention may also be used to assess the binding of small molecule substrates and ligands in, for example, cells, cell-free preparations, chemical libraries, and natural product mixtures. These substrates and ligands may be natural substrates and ligands, such as a response regulator, or may be structural or functional mimetics. See, e.g. Coligan et al., Current Protocols in Immunology 1(2): Chapter 5 (1991).

The invention also provides the use of the polypeptide, polynucleotide or inhibitor of the invention to interfere with the initial physical interaction between a pathogen and mammalian host responsible for sequelae of infection. In particular the molecules of the invention may be used: in the prevention of adhesion of bacteria, in particular bacteria, especially a gram positive bacteria, to mammalian extracellular matrix proteins on in-dwelling devices or to extracellular matrix proteins in wounds; to block Histidine Kinase protein-mediated mammalian cell invasion by, for example, initiating phosphorylation of mammalian tyrosine kinases (Rosenshine et al., Infect. Immun. 60:2211 (1992); to block bacterial adhesion between mammalian extracellular matrix proteins and bacterial Histidine Kinase proteins that mediate tissue damage and; to block the normal progression of pathogenesis in infections initiated other than by the implantation of in-dwelling devices or by other surgical techniques.

The antagonists and agonists of the invention may be employed, for instance, to inhibit bacterial growth or other metabolic function, especially of Staphylococcus aureus, as well as to treat or inhibit disease, such as, infections of the upper respiratory tract (e.g., otitis media, bacterial tracheitis, acute epiglottitis, thyroiditis), lower respiratory (e.g., empyema, lung abscess), cardiac (e.g., infective endocarditis), gastrointestinal (e.g., secretory diarrhoea, splenic absces, retroperitoneal abscess), CNS (e.g., cerebral abscess), eye (e.g., blepharitis, conjunctivitis, keratitis, endophthalmitis, preseptal and orbital cellulitis, darcryocystitis), kidney and urinary tract (e.g., epididymitis, intrarenal and perinephric absces, toxic shock syndrome), skin (e.g., impetigo, folliculitis, cutaneous abscesses, cellulitis, wound infection, bacterial myositis) bone and joint (e.g., septic arthritis, osteomyelitis), among other diseases.

Vaccines

Another aspect of the invention relates to a method for inducing an immunological response in an individual, particularly a mammal which comprises inoculating the individual with Histidine Kinase, or a fragment or variant thereof, adequate to produce antibody and/or T cell immune response to protect said individual from infection, particularly bacterial infection and most particularly Staphylococcus aureus infection. Also provided are methods whereby such immunological response slows bacterial replication. Yet another aspect of the invention relates to a method of inducing immunological response in an individual which comprises delivering to such individual a nucleic acid vector to direct expression of Histidine Kinase, or a fragment or a variant thereof, for expressing Histidine Kinase, or a fragment or a variant thereof in vivo in order to induce an immunological response, such as, to produce antibody and/or T cell immune response, including, for example, cytokine-producing T cells or cytotoxic T cells, to protect said individual from disease, whether that disease is already established within the individual or not. One way of administering the gene is by accelerating it into the desired cells as a coating on particles or otherwise. Such nucleic acid vector may comprise DNA, RNA, a modified nucleic acid, or a DNA/RNA hybrid.

A further aspect of the invention relates to an immunological composition which, when introduced into an individual capable or having induced within it an immunological response, induces an immunological response in such individual to a Histidine Kinase or protein coded therefrom, wherein the composition comprises a recombinant Histidine Kinase or protein coded therefrom comprising DNA which codes for and expresses an antigen of said Histidine Kinase or protein coded therefrom. The immunological response may be used therapeutically or prophylactically and may take the form of antibody immunity or cellular immunity such as that arising from CTL or CD4+ T cells.

A Histidine Kinase polypeptide or a fragment thereof may be fused with co-protein which may not by itself produce antibodies, but is capable of stabilizing the first protein and producing a fused protein which will have immunogenic and protective properties. Thus fused recombinant protein, preferably further comprises an antigenic co-protein, such as lipoprotein D from Hemophilus influenzae, Glutathione-S-transferase (GST) or beta-galactosidase, relatively large co-proteins which solubilize the protein and facilitate production and purification thereof. Moreover, the co-protein may act as an adjuvant in the sense of providing a generalized stimulation of the immune system. The co-protein may be attached to either the amino or carboxy terminus of the first protein.

Provided by this invention are compositions, particularly vaccine compositions, and methods comprising the polypeptides or polynucleotides of the invention and immunostimulatory DNA sequences, such as those described in Sato, Y. et al. Science 273: 352 (1996).

Also, provided by this invention are methods using the described polynucleotide or particular fragments thereof which have been shown to encode non-variable regions of bacterial cell surface proteins in DNA constructs used in such genetic immunization experiments in animal models of infection with Staphylococcus aureus will be particularly useful for identifying protein epitopes able to provoke a prophylactic or therapeutic immune response. It is believed that this approach will allow for the subsequent preparation of monoclonal antibodies of particular value from the requisite organ of the animal successfully resisting or clearing infection for the development of prophylactic agents or therapeutic treatments of bacterial infection, particularly Staphylococcus aureus infection, in mammals, particularly humans.

The polypeptide may be used as an antigen for vaccination of a host to produce specific antibodies which protect against invasion of bacteria, for example by blocking adherence of bacteria to damaged tissue. Examples of tissue damage include wounds in skin or connective tissue caused, e.g., by mechanical, chemical or thermal damage or by implantation of indwelling devices, or wounds in the mucous membranes, such as the mouth, mammary glands, urethra or vagina.

The invention also includes a vaccine formulation which comprises an immunogenic recombinant protein of the invention together with a suitable carrier. Since the protein may be broken down in the stomach, it is preferably administered parenterally, including, for example, administration that is subcutaneous, intramuscular, intravenous, or intradermal. Formulations suitable for parenteral administration include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the bodily fluid, preferably the blood, of the individual; and aqueous and non-aqueous sterile suspensions which may include suspending agents or thickening agents. The formulations may be presented in unit-dose or multi-dose containers, for example, sealed ampules and vials and may be stored in a freeze-dried condition requiring only the addition of the sterile liquid carrier immediately prior to use. The vaccine formulation may also include adjuvant systems for enhancing the immunogenicity of the formulation, such as oil-in water systems and other systems known in the art. The dosage will depend on the specific activity of the vaccine and can be readily determined by routine experimentation.

While the invention has been described with reference to certain Histidine Kinaseprotein, it is to be understood that this covers fragments of the naturally occurring protein and similar proteins with additions, deletions or substitutions which do not substantially affect the immunogenic properties of the recombinant protein.

Compositions, Kits and Administration

The invention also relates to compositions comprising the polynucleotide or the polypeptides discussed above or their agonists or antagonists or response regulators. The polypeptides of the invention may be employed in combination with a non-sterile or sterile carrier or carriers for use with cells, tissues or organisms, such as a pharmaceutical carrier suitable for administration to a subject. Such compositions comprise, for instance, a media additive or a therapeutically effective amount of a polypeptide of the invention and a pharmaceutically acceptable carrier or excipient. Such carriers may include, but are not limited to, saline, buffered saline, dextrose, water, glycerol, ethanol and combinations thereof. The formulation should suit the mode of administration. The invention further relates to diagnostic and pharmaceutical packs and kits comprising one or more containers filled with one or more of the ingredients of the aforementioned compositions of the invention.

Polypeptides and other compounds of the invention may be employed alone or in conjunction with other compounds, such as therapeutic compounds.

The pharmaceutical compositions may be administered in any effective, convenient manner including, for instance, administration by topical, oral, anal, vaginal, intravenous, intraperitoneal, intramuscular, subcutaneous, intranasal or intradermal routes among others.

In therapy or as a prophylactic, the active agent may be administered to an individual as an injectable composition, for example as a sterile aqueous dispersion, preferably isotonic.

Alternatively the composition may be formulated for topical application for example in the form of ointments, creams, lotions, eye ointments, eye drops, ear drops, mouthwash, impregnated dressings and sutures and aerosols, and may contain appropriate conventional additives, including, for example, preservatives, solvents to assist drug penetration, and emollients in ointments and creams. Such topical formulations may also contain compatible conventional carriers, for example cream or ointment bases, and ethanol or oleyl alcohol for lotions. Such carriers may constitute from about 1% to about 98% by weight of the formulation; more usually they will constitute up to about 80% by weight of the formulation.

For administration to mammals, and particularly humans, it is expected that the daily dosage level of the active agent will be from 0.01 mg/kg to 10 mg/kg, typically around 1 mg/kg. The physician in any event will determine the actual dosage which will be most suitable for an individual and will vary with the age, weight and response of the particular individual. The above dosages are exemplary of the average case. There can, of course, be individual instances where higher or lower dosage ranges are merited, and such are within the scope of this invention.

In-dwelling devices include surgical implants, prosthetic devices and catheters, i.e., devices that are introduced to the body of an individual and remain in position for an extended time. Such devices include, for example, artificial joints, heart valves, pacemakers, vascular grafts, vascular catheters, cerebrospinal fluid shunts, urinary catheters, continuous ambulatory peritoneal dialysis (CAPD) catheters.

The composition of the invention may be administered by injection to achieve a systemic effect against relevant bacteria shortly before insertion of an in-dwelling device. Treatment may be continued after surgery during the in-body time of the device. In addition, the composition could also be used to broaden perioperative cover for any surgical technique to prevent bacterial wound infections, especially Staphylococcus aureus wound infections.

Many orthopedic surgeons consider that humans with prosthetic joints should be considered for antibiotic prophylaxis before dental treatment that could produce a bacteremia. Late deep infection is a serious complication sometimes leading to loss of the prosthetic joint and is accompanied by significant morbidity and mortality. It may therefore be possible to extend the use of the active agent as a replacement for prophylactic antibiotics in this situation.

In addition to the therapy described above, the compositions of this invention may be used generally as a wound treatment agent to prevent adhesion of bacteria to matrix proteins exposed in wound tissue and for prophylactic use in dental treatment as an alternative to, or in conjunction with, antibiotic prophylaxis.

Alternatively, the composition of the invention may be used to bathe an indwelling device immediately before insertion. The active agent will preferably be present at a concentration of 1 μg/ml to 10 mg/ml for bathing of wounds or indwelling devices.

A vaccine composition is conveniently in injectable form. Conventional adjuvants may be employed to enhance the immune response. A suitable unit dose for vaccination is 0.5-5 μg/kg of antigen, and such dose is preferably administered 1-3 times and with an interval of 1-3 weeks. With the indicated dose range, no adverse toxicological effects will be observed with the compounds of the invention which would preclude their administration to suitable individuals.

Each reference cited herein is hereby incorporated by reference in its entirety. Moreover, each patent application to which this application claims priority is hereby incorporated by reference in its entirety.

EXAMPLES

The examples below are carried out using standard techniques, which are well known and routine to those of skill in the art, except where otherwise described in detail. The examples are illustrative, but do not limit the invention.

Example 1 Strain Selection, Library Production and Sequencing

The polynucleotide having the DNA sequence given in SEQ ID NO: 1 was obtained from a library of clones of chromosomal DNA of Staphylococcus aureus in E. coli. The sequencing data from two or more clones containing overlapping Staphylococcus aureus DNAs was used to construct the contiguous DNA sequence in SEQ ID NO: 1. Libraries may be prepared by routine methods, for example: Methods 1 and 2 below.

Total cellular DNA is isolated from Staphylococcus aureus WCUH 29 according to standard procedures and size-fractionated by either of two methods.

Method 1

Total cellular DNA is mechanically sheared by passage through a needle in order to size-fractionate according to standard procedures. DNA fragments of up to 11 kbp in size are rendered blunt by treatment with exonuclease and DNA polymerase, and EcoRI linkers added. Fragments are ligated into the vector Lambda ZapII that has been cut with EcoRI, the library packaged by standard procedures and E. coli infected with the packaged library. The library is amplified by standard procedures.

Method 2

Total cellular DNA is partially hydrolyzed with a one or a combination of restriction enzymes appropriate to generate a series of fragments for cloning into library vectors (e.g., RsaI, PalI, AluI, Bshl235I), and such fragments are size-fractionated according to standard procedures. EcoRI linkers are ligated to the DNA and the fragments then ligated into the vector Lambda ZapII that have been cut with EcoRI, the library packaged by standard procedures, and E. coli infected with the packaged library. The library is amplified by standard procedures.

    __________________________________________________________________________     #             SEQUENCE LISTING                                                 - (1) GENERAL INFORMATION:                                                     -    (iii) NUMBER OF SEQUENCES: 4                                              - (2) INFORMATION FOR SEQ ID NO:1:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #pairs    (A) LENGTH: 2700 base                                                          (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: double                                                       (D) TOPOLOGY: linear                                                 -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:                                  - GAATTCCTAT TGTAAGTTTG ATTGATGTTT GTGTAGGATA GTCTGTACTA AA - #TATAAGCC          60                                                                           - TAGTCCCATG CTTTCTTTTT GGTTATCTTT AAAATATTTA TTTGATCCTG TG - #TAAAAAGG         120                                                                           - CTCGAATATC TTTTGTTGTT CTTCTAAACT AATTCCAGGT CCTTCGTCTA TA - #ACGGCAAA         180                                                                           - TTCGATTTGT TCATAGCTAG CATAACGAAT AGATAAATTG ATTTTGGTGT CA - #GTAGAAGT         240                                                                           - GTGTTTAACT GCATTTTCAA TCAAATTGAA TAAAGCTTGT AAAATCAACT TA - #CTGTCAAT         300                                                                           - GTGTATAAAC TGTAAATTTA CGGAGGATGA TACAGTTATA CGCTTTTTTA AA - #TGGCGACG         360                                                                           - TTCTAAAATC ATATCGATTT CTTCTACTAA TTCACTAACG AGATAAGGTT GC - #AATTTTAT         420                                                                           - CTGAACATTT GATGACTGTA ATTTTGTTAA TGATAAAATA TTTGTCACTA AT - #AGATATAA         480                                                                           - ATACTGACTT TCTTGAAAAC TATGTACAAG TAATTGTTCC TTTTCTATGA TA - #GACATATC         540                                                                           - TTTACTATGT GATACTAAAA TATCTAAATT TCCCATAATT GTTGTTAACG GT - #GTACGTAT         600                                                                           - GTCATGCGAA ATTGATCTTA AAAAATTTGA ATGTGTCAGT TGACGTTCAG CC - #TGTAACAT         660                                                                           - GGATTCTCTC GTTTGTTTAA GTAACGTCAC ATTTTCAACG GCGAGAGAAA GT - #TCATTTAA         720                                                                           - CATTGATTCT AATATTGATG CATCATATGG ATTAATCACT TGAGAACTTT GG - #TAATCAAT         780                                                                           - GGCTAGAATG CCTTTAATCG GAGATGTGCC AATTGGTATC AACCATTTAT TA - #ATGCCTGG         840                                                                           - AAATGTATCT GTTGTTGCAC CAGCTTGTCT TTCATTTTTA ATTACCCAGC TT - #AATGCTTG         900                                                                           - TTCATGCTGT TGAGTCGTAT TATCGATATG GTTTTGCAAT GGTATTGTTT TA - #ATTACTTT         960                                                                           - CGATTGATTG ATAACGTATA TAGTAATTGA TTGTTGCAAT AATTGATTAA TT - #TGGTATCC        1020                                                                           - AGCATTTATT AGTAAGTTTT CAACTGTATA AGTTTGTTTA ATCGAATCAT TA - #AATTGAAA        1080                                                                           - TAATAAATCT GTACGATAAA GTTGCTTTTT AGTAATGGAG TATTGGAATT TA - #ATTTGTTT        1140                                                                           - TAATAAAGCA CTCGTTAAAA TACTTGTTAA AATGCTAACG ATAAATGTAA TA - #GGATAGTC        1200                                                                           - AAAGCGATAT ACTTCAAATG TATATCTAGG TTCCGTAAAA AAATAATTAA AA - #ACAAATAC        1260                                                                           - GTTAATAATT GCTGCTAAAA AGCCAATGAT GAAGGACCGC GTCCAAATGG AT - #AATAAAAT        1320                                                                           - GATGCCGATG AGAAAAATCA TTAAAATAAT CGTACTAGAC TCATGCTTAT CA - #AGTTGATA        1380                                                                           - AATCCACAGT CCCATCATTA CACAAATTAT TTGAATCAAA ATCATTTTTA AC - #ATATCTAT        1440                                                                           - GGCGAAACGT TTGCCTTTAG GACGATAGGG TGATTTGTTC ATTTTCAATT CA - #ACAGGTAT        1500                                                                           - TTGTTTGATT GGAACGATTT CGATTTTATA GCTATGTTCA AAGGACATTA AA - #TGGTCAAT        1560                                                                           - TAAAGGTGTA TTGAAAAAGT CTCGCCACTT ATTTCTAATA TGTTGTCCGA TA - #ATTAATTT        1620                                                                           - GGTTACATCT TGATTTTTAC ACCATTCGTC TAATCCTAAT GCAACGGTTT GG - #CTATAAAC        1680                                                                           - TACTTTTACT TTTGCTCCTA ATGATTTTGC AAGCATGAGA TGTTGATGCA CT - #TGCTTTTG        1740                                                                           - ACTATCTTTA TATTGCCTGT TTTTTTCGAA TACATCTATA TAAATAGCAG TG - #AACTTCGC        1800                                                                           - ATGTTCTTTT TGAGCAATAT GGAATGCCTC TTTAATTACT GCTTCATTAT AA - #ATGCTCCC        1860                                                                           - ACTAATTGCC ACAGCAATAT GAGGTTTGAG TGACGTTTTA TGGTTGTGTC GG - #ACTTTTTC        1920                                                                           - TTTATCACTC ATCAAGTCGG CAACTGTTCT TAACGTCAAT GTACGCAGTT CG - #CTTAGGTG        1980                                                                           - GGCATACGTA AAGAAATTAC TAAATGCTAC ATCTAGCCTA TCCTTTTTAT AT - #ACCTTGCC        2040                                                                           - AGCTTTTAAG CGTTTAATTA ATTGTTCAGG TGAGATATCT ACGACTTCTA AT - #ACATCGGC        2100                                                                           - GCTCATTATG AAATAGTCGG GTACACGTTC TTTAACATGT ACACCGGTCA TC - #AGTTCAAT        2160                                                                           - TTGACTACTT AAACTTTCAA TATGTTGAAT GTTCAAAGTG GTATGAACAT CG - #ATACCATG        2220                                                                           - ATTTAAAATT TCTTCAATAT CCATATATCG TTTCTCATGA CGATCTCTAG AA - #ATATTCGT        2280                                                                           - ATGTGCTAAC TCATCGATAA GTACTATTGT CGGCGATTCT TCGATTATGC GG - #TCGACATC        2340                                                                           - TAAATATTGA AAATGATGAC TACCATGTTT AGTAAAATTG GTTGTGATTT TA - #GGTAATTG        2400                                                                           - TTCAGCTAAT GCATTTGTTT CATCACGCTG ATGCGGTTCA ATATATCCTA TT - #TTAATATC        2460                                                                           - AACGTTACTT TGAAATAGTT CAATGGCATT TGAAAGCATC TCAAATGTTT TA - #CCAACACC        2520                                                                           - TGGACTGTAA CCGATGTAAA TTGTTAAAGA TCCACGCTTT TTTCCTATGT TT - #AGCGATTC        2580                                                                           - AGTGTTTGAC ATAACCTTCA CCTCGATAGC AATATCATAA TATTCTTCAC AA - #TTAAATGC        2640                                                                           - TATAAAATTT ATTTCTGCAT ACACATCTTA ATGATTTCTT AATAACTAAG TT - #TGAAAATT        2700                                                                           - (2) INFORMATION FOR SEQ ID NO:2:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #acids    (A) LENGTH: 861 amino                                                          (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                 -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:                                  - Met Ser Asn Thr Glu Ser Leu Asn Ile Gly Ly - #s Lys Arg Gly Ser Leu          #                15                                                            - Thr Ile Tyr Ile Gly Tyr Ser Pro Gly Val Gl - #y Lys Thr Phe Glu Met          #            30                                                                - Leu Ser Asn Ala Ile Glu Leu Phe Gln Ser As - #n Val Asp Ile Lys Ile          #        45                                                                    - Gly Tyr Ile Glu Pro His Gln Arg Asp Glu Th - #r Asn Ala Leu Ala Glu          #    60                                                                        - Gln Leu Pro Lys Ile Thr Thr Asn Phe Thr Ly - #s His Gly Ser His His          #80                                                                            - Phe Gln Tyr Leu Asp Val Asp Arg Ile Ile Gl - #u Glu Ser Pro Thr Ile          #                95                                                            - Val Leu Ile Asp Glu Leu Ala His Thr Asn Il - #e Ser Arg Asp Arg His          #           110                                                                - Glu Lys Arg Tyr Met Asp Ile Glu Glu Ile Le - #u Asn His Gly Ile Asp          #       125                                                                    - Val His Thr Thr Leu Asn Ile Gln His Ile Gl - #u Ser Leu Ser Ser Gln          #   140                                                                        - Ile Glu Leu Met Thr Gly Val His Val Lys Gl - #u Arg Val Pro Asp Tyr          145                 1 - #50                 1 - #55                 1 -        #60                                                                            - Phe Ile Met Ser Ala Asp Val Leu Glu Val Va - #l Asp Ile Ser Pro Glu          #               175                                                            - Gln Leu Ile Lys Arg Leu Lys Ala Gly Lys Va - #l Tyr Lys Lys Asp Arg          #           190                                                                - Leu Asp Val Ala Phe Ser Asn Phe Phe Thr Ty - #r Ala His Leu Ser Glu          #       205                                                                    - Leu Arg Thr Leu Thr Leu Arg Thr Val Ala As - #p Leu Met Ser Asp Lys          #   220                                                                        - Glu Lys Val Arg His Asn His Lys Thr Ser Le - #u Lys Pro His Ile Ala          225                 2 - #30                 2 - #35                 2 -        #40                                                                            - Val Ala Ile Ser Gly Ser Ile Tyr Asn Glu Al - #a Val Ile Lys Glu Ala          #               255                                                            - Phe His Ile Ala Gln Lys Glu His Ala Lys Ph - #e Thr Ala Ile Tyr Ile          #           270                                                                - Asp Val Phe Glu Lys Asn Arg Gln Tyr Lys As - #p Ser Gln Lys Gln Val          #       285                                                                    - His Gln His Leu Met Leu Ala Lys Ser Leu Gl - #y Ala Lys Val Lys Val          #   300                                                                        - Val Tyr Ser Gln Thr Val Ala Leu Gly Leu As - #p Glu Trp Cys Lys Asn          305                 3 - #10                 3 - #15                 3 -        #20                                                                            - Gln Asp Val Thr Lys Leu Ile Ile Gly Gln Hi - #s Ile Arg Asn Lys Trp          #               335                                                            - Arg Asp Phe Phe Asn Thr Pro Leu Ile Asp Hi - #s Leu Met Ser Phe Glu          #           350                                                                - His Ser Tyr Lys Ile Glu Ile Val Pro Ile Ly - #s Gln Ile Pro Val Glu          #       365                                                                    - Leu Lys Met Asn Lys Ser Pro Tyr Arg Pro Ly - #s Gly Lys Arg Phe Ala          #   380                                                                        - Ile Asp Met Leu Lys Met Ile Leu Ile Gln Il - #e Ile Cys Val Met Met          385                 3 - #90                 3 - #95                 4 -        #00                                                                            - Gly Leu Trp Ile Tyr Gln Leu Asp Lys His Gl - #u Ser Ser Thr Ile Ile          #               415                                                            - Leu Met Ile Phe Leu Ile Gly Ile Ile Leu Le - #u Ser Ile Trp Thr Arg          #           430                                                                - Ser Phe Ile Ile Gly Phe Leu Ala Ala Ile Il - #e Asn Val Phe Val Phe          #       445                                                                    - Asn Tyr Phe Phe Thr Glu Pro Arg Tyr Thr Ph - #e Glu Val Tyr Arg Phe          #   460                                                                        - Asp Tyr Pro Ile Thr Phe Ile Val Ser Ile Le - #u Thr Ser Ile Leu Thr          465                 4 - #70                 4 - #75                 4 -        #80                                                                            - Ser Ala Leu Leu Lys Gln Ile Lys Phe Gln Ty - #r Ser Ile Thr Lys Lys          #               495                                                            - Gln Leu Tyr Arg Thr Asp Leu Leu Phe Gln Ph - #e Asn Asp Ser Ile Lys          #           510                                                                - Gln Thr Tyr Thr Val Glu Asn Leu Leu Ile As - #n Ala Gly Tyr Gln Ile          #       525                                                                    - Asn Gln Leu Leu Gln Gln Ser Ile Thr Ile Ty - #r Val Ile Asn Gln Ser          #   540                                                                        - Lys Val Ile Lys Thr Ile Pro Leu Gln Asn Hi - #s Ile Asp Asn Thr Thr          545                 5 - #50                 5 - #55                 5 -        #60                                                                            - Gln Gln His Glu Gln Ala Leu Ser Trp Val Il - #e Lys Asn Glu Arg Gln          #               575                                                            - Ala Gly Ala Thr Thr Asp Thr Phe Pro Gly Il - #e Asn Lys Trp Leu Ile          #           590                                                                - Pro Ile Gly Thr Ser Pro Ile Lys Gly Ile Le - #u Ala Ile Asp Tyr Gln          #       605                                                                    - Ser Ser Gln Val Ile Asn Pro Tyr Asp Ala Se - #r Ile Leu Glu Ser Met          #   620                                                                        - Leu Asn Glu Leu Ser Leu Ala Val Glu Asn Va - #l Thr Leu Leu Lys Gln          625                 6 - #30                 6 - #35                 6 -        #40                                                                            - Thr Arg Glu Ser Met Leu Gln Ala Glu Arg Gl - #n Leu Thr His Ser Asn          #               655                                                            - Phe Leu Arg Ser Ile Ser His Asp Ile Arg Th - #r Pro Leu Thr Thr Ile          #           670                                                                - Met Gly Asn Leu Asp Ile Leu Val Ser His Se - #r Lys Asp Met Ser Ile          #       685                                                                    - Ile Glu Lys Glu Gln Leu Leu Val His Ser Ph - #e Gln Glu Ser Gln Tyr          #   700                                                                        - Leu Tyr Leu Leu Val Thr Asn Ile Leu Ser Le - #u Thr Lys Leu Gln Ser          705                 7 - #10                 7 - #15                 7 -        #20                                                                            - Ser Asn Val Gln Ile Lys Leu Gln Pro Tyr Le - #u Val Ser Glu Leu Val          #               735                                                            - Glu Glu Ile Asp Met Ile Leu Glu Arg Arg Hi - #s Leu Lys Lys Arg Ile          #           750                                                                - Thr Val Ser Ser Ser Val Asn Leu Gln Phe Il - #e His Ile Asp Ser Lys          #       765                                                                    - Leu Ile Leu Gln Ala Leu Phe Asn Leu Ile Gl - #u Asn Ala Val Lys His          #   780                                                                        - Thr Ser Thr Asp Thr Lys Ile Asn Leu Ser Il - #e Arg Tyr Ala Ser Tyr          785                 7 - #90                 7 - #95                 8 -        #00                                                                            - Glu Gln Ile Glu Phe Ala Val Ile Asp Glu Gl - #y Pro Gly Ile Ser Leu          #               815                                                            - Glu Glu Gln Gln Lys Ile Phe Glu Pro Phe Ty - #r Thr Gly Ser Asn Lys          #           830                                                                - Tyr Phe Lys Asp Asn Gln Lys Glu Ser Met Gl - #y Leu Gly Leu Tyr Leu          #       845                                                                    - Val Gln Thr Ile Leu His Lys His Gln Ser As - #n Leu Gln                      #   860                                                                        - (2) INFORMATION FOR SEQ ID NO:3:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #pairs    (A) LENGTH: 740 base                                                           (B) TYPE: nucleic acid                                                         (C) STRANDEDNESS: double                                                       (D) TOPOLOGY: linear                                                 -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:                                  - AGGAGACGGT ATAATGCAAT CTAAAATATT GATAATTGAA GATGATCACG CA - #ATCACACA          60                                                                           - TTTACTTGAT GTTGCATTAA CTTTAGATTA TTACAATGTA ACTACAGCCG AC - #AATGCCAC         120                                                                           - ACAAGCACAC TTTAAAATTC AAATTGATAA ACCAGATGTC ATTTTATTAG AT - #TTAGGTTT         180                                                                           - ACCAGATAAA GATGGATTAT GTTTGATTTC AGAAATCAGG CAACATACTG AC - #ATTCCTAT         240                                                                           - CATTGTAATA AGTGCAAGAC AAGAAGAACA CACAATTATT CAAGCTTTAG AT - #ATCGGTGC         300                                                                           - GAATGACTAT ATGACTAAAC CTTTTAATGT TGATGAGCTT CGGGCACGAA TA - #CGAGTCAT         360                                                                           - CGAGAGAATC GCTAAGTCAC ATCAAGAAAC TAACATTGTA TTTACTAACG GT - #TTGCTAAG         420                                                                           - CATCGACTTT GGCTCCAAAT CTGTTGTTAT TAATAATCAG GAGGTACATT TG - #ACGCCAAA         480                                                                           - TGAATTTAGC TTGTTAGAAC TATTGTCAAA TCATAAAGGA AAAGTACTCA CT - #TATGAGAT         540                                                                           - GATATTAAAA CGAATATATG GCTATGTTAA TAAGACTGAA ATGCCTAGTT TA - #AGAGTGCA         600                                                                           - TATGACATCA TTAAGACAAA AACTTTCACA ATGTCATGAG GACGCAAAAG AT - #ATTATTAA         660                                                                           - AACACATCCA CGCATTGGTT ATCAAATGTT GCAGTGGAAA GAGAAATAAT TA - #AATAAAAA         720                                                                           #740               ACGA                                                        - (2) INFORMATION FOR SEQ ID NO:4:                                             -      (i) SEQUENCE CHARACTERISTICS:                                           #acids    (A) LENGTH: 231 amino                                                          (B) TYPE: amino acid                                                           (C) STRANDEDNESS: single                                                       (D) TOPOLOGY: linear                                                 -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:                                  - Met Gln Ser Lys Ile Leu Ile Ile Glu Asp As - #p His Ala Ile Thr His          #                15                                                            - Leu Leu Asp Val Ala Leu Thr Leu Asp Tyr Ty - #r Asn Val Thr Thr Ala          #            30                                                                - Asp Asn Ala Thr Gln Ala His Phe Lys Ile Gl - #n Ile Asp Lys Pro Asp          #        45                                                                    - Val Ile Leu Leu Asp Leu Gly Leu Pro Asp Ly - #s Asp Gly Leu Cys Leu          #    60                                                                        - Ile Ser Glu Ile Arg Gln His Thr Asp Ile Pr - #o Ile Ile Val Ile Ser          #80                                                                            - Ala Arg Gln Glu Glu His Thr Ile Ile Gln Al - #a Leu Asp Ile Gly Ala          #                95                                                            - Asn Asp Tyr Met Thr Lys Pro Phe Asn Val As - #p Glu Leu Arg Ala Arg          #           110                                                                - Ile Arg Val Ile Glu Arg Ile Ala Lys Ser Hi - #s Gln Glu Thr Asn Ile          #       125                                                                    - Val Phe Thr Asn Gly Leu Leu Ser Ile Asp Ph - #e Gly Ser Lys Ser Val          #   140                                                                        - Val Ile Asn Asn Gln Glu Val His Leu Thr Pr - #o Asn Glu Phe Ser Leu          145                 1 - #50                 1 - #55                 1 -        #60                                                                            - Leu Glu Leu Leu Ser Asn His Lys Gly Lys Va - #l Leu Thr Tyr Glu Met          #               175                                                            - Ile Leu Lys Arg Ile Tyr Gly Tyr Val Asn Ly - #s Thr Glu Met Pro Ser          #           190                                                                - Leu Arg Val His Met Thr Ser Leu Arg Gln Ly - #s Leu Ser Gln Cys His          #       205                                                                    - Glu Asp Ala Lys Asp Ile Ile Lys Thr His Pr - #o Arg Ile Gly Tyr Gln          #   220                                                                        - Met Leu Gln Trp Lys Glu Lys                                                  225                 2 - #30                                                    __________________________________________________________________________ 

What is claimed is:
 1. An immunological composition comprising a DNA that codes for and expresses a histidine kinase polynucleotide comprising SEQ ID NO: 1 or a histidine kinase protein coded therefrom wherein the immunological composition, when introduced into a mammal, induces an immunological response in the mammal to the histidine kinase polynucleotide or protein coded therefrom.
 2. An isolated polynucleotide comprising a first polynucleotide or the full complement of the entire length of the first polynucleotide, wherein the first polynucleotide comprises the nucleotide sequence set forth in SEQ ID NO:
 1. 3. The isolated polynucleotide of claim 2, wherein the isolated polynucleotide comprises the first polynucleotide.
 4. A vector comprising the isolated polynucleotide of claim
 3. 5. An isolated host cell comprising the vector of claim
 4. 6. A process for producing a polypeptide comprising the step of culturing the host cell of claim 5 under conditions suitable for the production of the polypeptide, wherein the polypeptide is encoded by the first polynucleotide.
 7. The isolated polynucleotide of claim 2, wherein the isolated polynucleotide comprises the full complement of the entire length of the first polynucleotide.
 8. A vector comprising the isolated polynucleotide of claim
 7. 9. An isolated host cell comprising the vector of claim
 8. 10. An isolated polynucleotide comprising a first polynucleotide or the full complement of the entire length of the first polynucleotide, wherein the first polynucleotide encodes a polypeptide consisting of the amino acid sequence set forth in SEQ ID NO:
 2. 11. The isolated polynucleotide of claim 10, wherein the isolated polynucleotide comprises the first polynucleotide.
 12. A vector comprising the isolated polynucleotide of claim
 11. 13. An isolated host cell comprising the vector of claim
 12. 14. A process for producing a polypeptide comprising the step of culturing the host cell of claim 13 under conditions suitable for the production of the polypeptide, wherein the polypeptide is encoded by the first polynucleotide.
 15. The isolated polynucleotide of claim 10, wherein the isolated polynucleotide comprises the full complement of the entire length of the first polynucleotide.
 16. A vector comprising the isolated polynucleotide of claim
 15. 17. An isolated host cell comprising the vector of claim
 16. 18. A method for producing antibodies in a mammal comprising: delivering to a tissue of the mammal a nucleic acid vector to direct expression in vivo of a polypeptide from apolynucleotide of claim 10, wherein the polypeptide is effective to induce an immunological response to the polypeptide of SEQ ID NO: 2; and, wherein the polypeptide is expressed in vivo and induces an immunological response to produce antibodies to the polypeptide of SEQ ID NO:
 2. 